Dosa on Valencia had the distinction of being San Francisco's first South Indian restaurant when it opened in 2005, but its look and sophistication were eclipsed by its more grown-up sister that opened on Fillmore three years later.

Now the older and littler sis - still my favorite - has been given a face-lift and a full liquor license to create the Spice Route cocktails that have become mainstays at the larger, more elaborate location.

With the re-do, the Valencia location isn't far behind in the looks department, either. Elongated, shimmering chandeliers with gold metal squares and crystal teardrops hang over the bar, the floor is covered in glossy tiles, and the walls painted a Golden Gate Bridge color. It all works to give the interior a designed, upscale appeal.

As Indian restaurants go, the menu is fairly compact, and chef Paul Raj seems to show his talent on just about every dish. That applies to the traditional sambar, a spicy lentil stew that accompanies the dosas, as well as to more creative combinations, such as a watermelon salad ($9), where the chunks of fruit match with warm sauteed squares of paneer, sprouted lentils and fresh coconut. It's a cooling foil to some of the spicier dishes that generously pepper the menu.

Raj doesn't shy away from the heat that characterizes South India dishes. One of my favorite soups has always been the rasam Fire Broth ($4), a sinus-clearing concoction of lentils and tomatoes, with tamarind lending a pleasantly sour note to the gently smoldering heat.

On my Update visit, I went for seasonality with the corn soup ($9), a thick puree of grilled kernels smoothed with coconut milk and accented with fresh curry leaves. At first all that was apparent was the deceptive sweetness of the corn and the creaminess of the blend, but soon the slow sear began to creep up the tongue, prodding me to take another taste and start the process over again.

The kitchen also knows how to fry, whether it's the chile-marinated fish fingers ($11) flavored with ginger, cumin and garlic; chunks of Chennai organic chicken ($9.50), marinated in Straus yogurt spiced with cumin and coriander and fried to a bronzed perfection; or the chile and onion pakora that look a little like deep-fried tarantulas in a bowl. The onions are thinly sliced and coated in chickpea flour that gives them the unusual shape, then are tossed with a few flash-fried curry leaves.

When it comes to curries, I was a little disappointed in the Tamil lamb ($18) because there was very little meat and the sauce was muddled, not nearly as vibrant as I remember. It reminded me of those generic Indian buffets where things can sit a little too long and wind up with the same texture.

However, that wasn't the case with the seasonal vegetable bhatura ($13) with green beans, cauliflower, squash and other vegetables in a red curry with a huge puff of fried wheat bread. I also appreciated the prawn moilee ($15), where the flavor of coconut played off fenugreek and ginger, creating a golden sauce that boosted the sweet flavor of the prawns.

All the dosas here are superb, including the crisp, loosely rolled wafer that hangs over the plate in the masala dosa ($10), or the more pancake-like rolls with peas and paneer ($11).

The restaurant has also upped the dessert offerings, using Indian ingredients in a more Western approach such as a fresh coconut cake ($8) infused with curry leaf syrup, and a beautifully executed tart tatin topped with mango and chile ($9) and served with caramel sauce and a yogurt mousse. I loved the idea of the cool passion fruit custard ($9) that was supposed to be served with warm tapioca, but unfortunately they were the same cool temperature, so the contrast wasn't dramatic.

Service at Dosa has always been helpful, but somewhat forgetful. Staff members know the menu and can help inexperienced diners make their way through the selections, but at times they can become distracted. On one visit, for example, we never received a dish we had ordered, and on another we chose a Gruner Veltliner from the well-crafted wine list, but we had to remind the waiter about it after we had eaten several appetizers.

Yet for the most part, the recent improvements to the original Dosa have made the experience even more pleasant without losing the character of the food. Under Raj, that food is moving toward three-star status.

Prices are based on main courses. When entrees fall between these categories, the prices of appetizers help determine the dollar ratings. Chronicle critics make every attempt to remain anonymous. All meals are paid for by The Chronicle. Star ratings are based on a minimum of three visits. Ratings are updated continually based on at least one revisit.

Michael Bauer is The Chronicle's restaurant critic. E-mail him at mbauer@sfchronicle.com, and go to sfgate.com/food to read his previous reviews. Find his blog daily at insidescoopsf.com, and follow him on Twitter at @michaelbauer1.